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From 3f31f7d9b5404a10648abe536c8b408bfb4502e1 Mon Sep 17 00:00:00 2001
From: Hans de Goede <hdegoede@redhat.com>
Date: Sun, 28 Jun 2020 17:52:29 +0200
Subject: [PATCH] ASoC: rt5670: Fix dac- and adc- vol-tlv values being off by a factor of 10
Git-commit: 3f31f7d9b5404a10648abe536c8b408bfb4502e1
Patch-mainline: v5.8-rc7
References: jsc#SLE-16518

The adc_vol_tlv volume-control has a range from -17.625 dB to +30 dB,
not -176.25 dB to + 300 dB. This wrong scale is esp. a problem in userspace
apps which translate the dB scale to a linear scale. With the logarithmic
dB scale being of by a factor of 10 we loose all precision in the lower
area of the range when apps translate things to a linear scale.

E.g. the 0 dB default, which corresponds with a value of 47 of the
0 - 127 range for the control, would be shown as 0/100 in alsa-mixer.

Since the centi-dB values used in the TLV struct cannot represent the
0.375 dB step size used by these controls, change the TLV definition
for them to specify a min and max value instead of min + stepsize.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Link: https://lore.kernel.org/r/20200628155231.71089-5-hdegoede@redhat.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 sound/soc/codecs/rt5670.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/sound/soc/codecs/rt5670.c b/sound/soc/codecs/rt5670.c
index f21181734170..dfbc0ca38ff7 100644
--- a/sound/soc/codecs/rt5670.c
+++ b/sound/soc/codecs/rt5670.c
@@ -603,9 +603,9 @@ int rt5670_set_jack_detect(struct snd_soc_component *component,
 EXPORT_SYMBOL_GPL(rt5670_set_jack_detect);
 
 static const DECLARE_TLV_DB_SCALE(out_vol_tlv, -4650, 150, 0);
-static const DECLARE_TLV_DB_SCALE(dac_vol_tlv, -65625, 375, 0);
+static const DECLARE_TLV_DB_MINMAX(dac_vol_tlv, -6562, 0);
 static const DECLARE_TLV_DB_SCALE(in_vol_tlv, -3450, 150, 0);
-static const DECLARE_TLV_DB_SCALE(adc_vol_tlv, -17625, 375, 0);
+static const DECLARE_TLV_DB_MINMAX(adc_vol_tlv, -1762, 3000);
 static const DECLARE_TLV_DB_SCALE(adc_bst_tlv, 0, 1200, 0);
 
 /* {0, +20, +24, +30, +35, +40, +44, +50, +52} dB */
-- 
2.16.4